Trends in thyroid hormone prescribing and consumption in the UK

BMC Public Health Trends in thyroid hormone prescribing and consumption in the UK Anna L Mitchell 1 Bryan Hickey 0 Janis L Hickey 0 Simon HS Pearce 1 0 British Thyroid Foundation , 3 Devonshire Place, Harrogate, HG1 4AA , UK 1 Endocrine Unit, Royal Victoria Infirmary and Institute of Human Genetics, Newcastle University , Newcastle upon Tyne, NE1 4LP , UK Background: Thyroid hormone replacement is one of the most commonly prescribed and cost effective treatments for a chronic disease. There have been recent changes in community prescribing policies in many areas of the UK that have changed patient access to necessary medications. This study aimed to provide a picture of thyroid hormone usage in the UK and to survey patient opinion about current community prescribing policies for levothyroxine. Methods: Data on community prescriptions for thyroid hormones in England between 1998 and 2007, provided by the Department of Health, were collated and analysed. A survey of UK members of a patient support organisation (the British Thyroid Foundation) who were taking levothyroxine was carried out. Results: The amount of prescribed thyroid hormones used in England has more than doubled, from 7 to almost 19 million prescriptions, over the last 10 years. The duration of prescriptions has reduced from 60 to 45 days, on average over the same time. Two thousand five hundred and fifty one responses to the patient survey were received. Thirty eight percent of levothyroxine users reported receiving prescriptions of 28 days' duration. 59% of respondents reported being dissatisfied with 28-day prescribing. Conclusion: Amongst users of levothyroxine, there is widespread patient dissatisfaction with 28day prescription duration. Analysis of the full costs of 28-day dispensing balanced against the potential savings of reduced wastage of thyroid medications, suggests that this is unlikely to be an economically effective public health policy. - Background Since 1968, most forms of hormone replacement therapy, including levothyroxine, have been dispensed free of charge to NHS patients in England and Wales, under the medical exemption scheme. Thus, patients taking essential medications have been able to access a continuous supply, irrespective of their means. Patients with both autoimmune and congenital hypothyroidism require thyroid hormone replacement, in addition to those who have had surgical thyroidectomy or ablative radioiodine treatment for hyperthyroidism and thyroid cancer. Since hypothyroidism from all these causes is a chronic and irreversible condition, the majority of hypothyroid patients will require lifelong thyroid hormone treatment. About 19 million prescriptions for thyroid hormone preparations were dispensed in England during 2007, making it one of the most frequently prescribed medications[1]. From the above data, one can estimate that slightly over 3% of the population of England were prescribed regular levothyroxine during 2007[2]. This is corroborated by a prevalence rate for hypothyroidism of 3.01% in Tayside, Scotland during 2001[3]. Hypothyroidism as a clinical syndrome was first recognised in the 1870s and its subsequent treatment with extract of animal thyroid was first achieved in Newcastle upon Tyne during the 1890s by Murray[4]. Synthetic thyroid hormone replacement therapy has been available since 1927, when British chemists Harington and Barger first synthesised thyroxine[5]. So, for more than 50 years, thyroid hormone replacement has predominantly been formulated as synthetic levothyroxine (T4). Nevertheless, in recent years there has been a minor trend away from levothyroxine monotherapy in the treatment of hypothyroidism. This has taken two distinct forms: use of triiodothyronine (liothyronine, T3) either as monotherapy, or more commonly combined with levothyroxine (T3/ T4); and use of desiccated porcine thyroid (marketed as Armour 'Natural' thyroid). The use of combined T3/T4 was re-explored following a small but high profile study of thyroid cancer patients who were swapped from suppressive levothyroxine therapy, to a lesser dose of combined T3/T4[6]. Subsequent to this study, a further 10 larger studies, involving, in total, more than 1000 patients largely with autoimmune hypothyroidism, have failed to reproduce a benefit from combined T3/T4[7]. Nevertheless, there is no current formulation of T3/T4 that replicates the natural pattern and relative quantities of these hormones released from the human thyroid, and a slow release preparation might have utility in the future. The movement towards use of porcine thyroid extract in the UK has been largely patient-led, with the support of a few fringe practitioners, with many patients believing there could be some additional benefit from use of a 'natural' preparation compared to use of synthetic hormones. As there has never been a randomised trial of levothyroxine versus porcine thyroid extract, any possible health benefit remains uncharacterised, although most conventional practitioners have been cautious to recommend such therapy, as porcine thyroid is known to synthesise substantially more T3 than human thyroid[8]. In addition, porcine thyroid extract is substantially more expensive than the 4 pence for a 100 microgram levothyroxine tablet. As concerns grow over increasing healthcare costs, local primary care organisations (PCOs) have developed strategies aimed at rationalising resource use and providing good value in health care spending. Prescription drug wastage and over-prescribing have been identified as particular targets for this economy drive, and over the last 5 years many PCOs have implemented new initiatives to reduce drug costs. One such strategy has been for PCOs to recommend that GPs prescribe only a 28-day supply of medication at one time. This 28-day prescribing policy followed several studies which demonstrated that restricted and closely monitored prescribing periods reduced over-prescribing and medicine wastage[9-11]. One scheme introduced in Kirklees estimated that by doing this, drug wastage would be reduced by approximately 33%[11]. Nevertheless, most PCOs have recognised that for certain medications, most notably oral contraceptives, the detrimental effect of an interrupted patient supply would not be acceptable, and therefore exempted these from the policy. In a similar way, several PCOs have seen that for inexpensive and long-term medications (eg. oestrogen hormone replacement), there are few savings to be made and have exempted these from the 28-day prescribing policy. However, many practices in the UK have applied the 28-day prescription recommendation indiscriminately and without flexibility, and this may have had an untoward effect on numerous patients taking long-term medications, including levothyroxine. The impact of this prescribing policy on, and its acceptability with, patients taking regular medications has never been evaluated. In this paper, we document the trends (...truncated)